Magnetically selected gate



Dec. 31, 1968 G. MOHNKERN 3,419,854

MAGNETICALLY SELECTED GATE 7 Filed Dec. 28, 1964 INVENTOR, GERALD L. MOHNKERN.

BY. #4,? 7w! M M flu 9 My. 8. A l/ M1 ATTORNEYS United States Patent Oil ice 3,419,854 Patented Dec. 31, 1968 3,419,854 MAGNETICALLY SELECTED GATE Gerald L. Mohnkern, Las Cruces, N. Mex., assignor to the United States of America as represented by the Secretary of the Anny Filed Dec. 28, 1964. Ser. No. 421,736 5 Claims. (Cl. 340-174) ABSTRACT OF THE DISCLOSURE This invention relates to a matrix network of circuits coupled at given intervals by saturable cores in a matrix configuration oriented in a plane. A flexible strip of permanently-magnetized material is positioned in any desired curve or configuration of curves along the surface of said plane to saturate a given sequence of the saturable cores, to reduce the inductive coupling of the circuits corresponding to said given sequence.

BACKGROUND OF THE INVENTION The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royality thereon.

The use of cores to couple crossed conductors in a matrix is well known and the cores and conductor crossings of such systems may be oriented in many ways to represent many types of data, or information that is to be stored and remembered for future use. Cores may be provided for all the conductor crossings in a matrix, and the cores may be set, magnetically, in either of the possible polarities by the flow of current of suitable magnitude and direction through one or more of the writing conductors that pass through the desired cores. The magnetic state of the various cores provides a corresponding effect in the reading conductors, and the many possible combinations of magnetic states of the cores provide as many discrete units of information that may be stored. Or, cores may be provided at only those conductor crossings that are needed to inductively couple certain conductors to provide a particular pattern.

However, it would be difiicult, if not impractical, to change the cores of a large matrix to produce an irregular pattern, and it would be impossible to set up certain irregular patterns by electrical means.

It is therefore an object of this invention to provide an improved matrix control system.

It is a further object of this invention to provide an improved matrix control system having an external, magneto-mechanical means for producing an irregular magnetic pattern in the cores of the matrix.

These and other objects are accomplished by providing a matrix of saturable cores, intersected by both X and Y coordinate conductors or lines. The magnetic state of the cores is controlled by a flexible strip of permanently magnetized material with a flux density high enough to saturate any of the cores in its immediate vicinity. The flexible strip is formed into any desired curve and positioned in a plane parallel to and adjacent to the plane of the matrix in order to saturate cores of the matrix corresponding to the desired curve.

When one of the lines of one of the sets of coordinate conductors is pulsed, all of the lines of the other set of coordinate conductors that have a common core, will have an induced voltage, except where the common core or cores are saturated by the magnetized strip.

This invention will be better understood and other objects of this invention will become more apparent from the following specification and the drawings, in which;

FIG. 1 shows the combination of a matrix of saturable cores, conductors, and a magnetized strip in accordance with this invention; and

FIG. 2 shows a typical one of the saturable cores coupling two typical intersecting conductors or lines of the matrix.

Referring now more particularly to FIG. 1, the matrix 10 has one series of lines 12, along one direction, that may be considered the X coordinate lines or the input lines. The matrix has another series of lines 14, along another direction, that may be considered the Y coordinate lines or the output lines. Annular cores 16 physically and inductively couple one of the conductors of both the input and the output lines at each of the intersections.

The lines and cores of the matrix may be imbedded in a potting compound 18 for mechanical convenience; to hold the matrix in the desired plane and to provide a fiat surface for effective positioning of the magnetized strip 20.

A portion of the potting compound is shown cut away at 19 to more clearly show the intersecting lines and the corresponding cores.

A single one of these cores and its intersecting conductors is shown in FIG. 2, in an enlarged scale and without the potting compound. In FIG. 2 the conductor 12 may be considered as one of the lines 12 of FIG. 1, the conductor 14 may be considered as one of the lines 14 of FIG. 1, and the core 16 may be considered as one of the cores 16 of FIG. 1.

It is quite obvious from either FIG. 1 or 2 that a pulse of current in any one of the conductors 12 will cause a change in the flux of the core or cores 16 through which it passes, which will induce a corresponding current in any or all of the other intersecting conductors 14 passing through the proper cores. It will also be apparent that, if any of the cores 16 is saturated, a pulse of current in the one of the conductors 12 through the saturated core will not induce a corresponding current in the one of the intersecting conductors 14 passing through the same, saturated coreunless the current through the conductor 12 is sufficient to unsaturate the core, which is not the case here.

In operation the magnetized strip 20 is positioned along the surface of the body of the matrix. It may be positioned in any desired curve. The magnetic field strength of the magnetic strip must be suflicient to saturate all of the cores that it passes over or comes close to. The magnetic field strength must also be strong enough to maintain the appropriate cores in a state of saturation when currents are passed through the conductors 12 and these currents, in turn, must be of sutficient magnitude to induce a usable current in the corresponding crossings of conductors 14 in all of the unsaturated cores.

The saturation of specific cores reduces the inductive coupling provided by these cores to the point whereat there will be no appreciable current induced in the conductor 14 passing through a saturated core by the current in the conductor 12 of the same core. Consequently, by sampling each of the conductors 12, in turn, the pattern of responses of the conductors 14 will represent the position of the magnetized strip.

It will be obvious to anyone skilled in the art that the matrix is not limited to the number of lines and cores shown here, nor to the general orientation of these elements. Additional lines from a third set of coordinate conductors may also be woven through the cores in a regular or an irregular pattern.

The lines are not limited to solid straight conductors, as are shown here for simplicity. Each conductor may have any desired number of turns around each of the cores in its path in a well-known manner to increase the inductive effect.

The magnetized strip may be flexible enough to assume any variety of shapes and forms. It may also be preformed 3 into a rigid strip of any desired shape, or it may be combined with other rigid or flexible strips or other magnetized shapes for special effects.

The flexible strip may be made of small, steel, permanent, bar magnets, flexibly connected together, in a manner similar to the flexible stirp commonly used in refrigerator doors.

The surface of the matrix unit may be flat, or ridged, or indented in any desired way to best accommodate the strip or to hold it in a desired position. A visible grid or other device may be inscribed on the surface of the matrix unit to facilitate the exact placement of the strip with relation to the cores and intersections of the matrix.

The potting compound may be permanent, or it may be removable by heat or chemical action to permit repairs or modifications to be made in the matrix. The potting compound may be of any of the well-known non-magnetic types, or it may include ferrous compounds to increase the effect of the magnetic strip or the coupling between the conductors.

In the specific embodiment described in the foregoing specification, the cores were of the general ceramic type H feramic .0025 inch thick, having an .08 inch outside diameter and a .05 inch inside diameter. The types MC-l03, 119 or 140 memory cores made by General Ceramics may also be used. The S loop cores are preferable to the H loop cores because they have less stringent drive requirements.

The conductors may be of any suitable, low resistance material and they may be coupled to any of the wellknown core driving circuits used in magnetic core mem ories or digital tape recorders. The current requirements are generally lower than for memory core circuitry.

What is claimed is:

1. In combination with a matix of crossed conductors passing through saturable cores at each intersection of said crossed conductors; an elongated, highly-flexible continuously-magnetized strip positioned along the surface of said matrix; said strip being adaptable to be curved in any continuous patten including any desired portion or combination of portions of said surface of said matrix; and said magnetic strip having sufficient magnetic strength to saturate any of said cores of said matrix adjacent to said strip.

2. In combination with a matrix having crossed conductors passing through a saturable, toroidal core at each intersection; a plurality of penrnanent magnets, closely spaced within an elongated highly-flexible strip; said strip being positioned along the surface of said matrix; said strip being adaptable to be curved in any continuous pattern including any desired portion or combination of portions of said surface of said matrix; and said magnets having suflicient magnetic strength to saturate any of said cores of said matrix adjacent to said strip.

3. A matrix comprising a plurality of crossed conductors; a plurality of cores inductively coupling said conductors at each of the intersections of said crossed conductors; a plurality of permanent magnets, closely spaced Within an elongated highly-flexible strip; said strip being positioned in close proximity to said cores; said strip being adaptable to be curved in any continuous pattern including any desired portion or combination of portions of said close proximity to said cores; and said magnets having sufficient magnetic strength to saturate any of said cores of said matrix adjacent to said strip.

4. A switching system for a magnetic memory matrix comprising a plurality of cores, geometrically oriented in a common plane, each of said cores having an input winding and an output winding inductively coupled by said core; and an elognated highly-flexible continuouslymagnetized strip physically positionable along said common plane of said cores in said matrix, said strip being adaptable to be curved in any desired portion or combination of portions of said common plane, said magnetic strip having sufiicient magnetic strength to saturate any of said cores within a given distance from said strip.

5. In a matrix comprising a plurality of toroidal cores, positioned in a substantially uniform plane, in a geometric pattern; a first group of conductors positioned parallel to each other, each of said conductors of said first group passing through a separate series of said cores in a first direction; a second group of conductors, positioned parallel to each other and perpendicular to said first direction, each of said conductors of said second group passing through a separate series of said cores comprising certain of those of said cores that said first group of conductors pass through; and an elongated highly-flexible, magnetic strip positioned adjacent to said uniform plane to saturate those of said cores in said plane that are adjacent to said magnetic strip; said strip being adaptable to be curved in any continuous pattern including any desired portion or combination of portions of said uniform plane.

References Cited UNITED STATES PATENTS 3,140,403 7/1964 Morwald 340174 STANLEY M. URYNOWICZ, JR., Primary Examiner.

B. L. HALEY, Assistant Examiner. 

